The meteor that crashed into Russia "was the largest recorded object to strike the Earth in more than a century," Nature reports. It released more energy than the nuclear weapon tested by North Korea a few days ago.
That raises another interesting point -- most of the thousands of damaged apartments and buildings were hit by shock waves from the explosion of the rock breaking up in the atmosphere, not the actual fragments, or meteorites, hitting the ground.
[Margaret Campbell-Brown, an astronomer at the University of Western Ontario in London, Canada] says that the infrasound data shows a very shallow angle of approach — a feature that funnelled much of the energy from the blast to the city below. Still, she adds, "It's lucky that there wasn't more damage."